Formulation for corn oil recovery and method of use thereof

ABSTRACT

Provided is a method for recovering oil from corn to ethanol production, the method comprising applying a formulation comprising (i) a compound of formula (I), in which R 1 -R 3  are defined herein, (ii) an oil, and (iii) a metal oxide to a corn-based product from an ethanol production process. Also provided is a formulation effective for corn oil recovery comprising (i) a mixture of ethoxylated C 14-18  mono- and diglycerides, (ii) an oil, and (iii) a metal oxide.

BACKGROUND OF THE INVENTION

Corn oil has gained considerable momentum for use as a biodiesel. Corn oil also is used extensively in animal (e.g., poultry, swine, and cattle) feed. Thus the ability to obtain oil as part of the ethanol recovery process from corn is more important than ever. For every bushel of corn, there is approximately 1.5 pound of corn oil available for extraction.

To obtain ethanol and oil, a corn kernel typically undergoes fractionation to separate the various parts of the kernel: endosperm, germ, and the outer skin known as bran. To produce ethanol, starch contained in the endosperm must be fermented, whereas the corn's germ contains about 85% of the kernel's oil. Corn oil typically is obtained by pressing fractionated corn particles and extracting the oil with a solvent, such as hexane. To isolate the corn oil, the solvent is evaporated, recovered, and recycled. However, this method can be undesirable with respect to the use of organic solvent and the percent oil recovery is not very high.

Thus there remains a need to improve corn processing to improve the oil yield of the process and/or avoid the use of organic solvent.

BRIEF SUMMARY OF THE INVENTION

The invention provides a method for recovering oil from corn to ethanol production by applying a formulation comprising

(i) a compound of formula (I),

wherein

R¹ is a fatty acid residue,

R² and R³ are the same or different and each is a polyalkoxy group or —C(O)R¹, provided that at least one of R² and R³ is a polyalkoxy group,

(ii) an oil, and

(iii) a metal oxide

to a corn-based product from an ethanol production process.

The invention further provides a formulation comprising (i) a mixture of ethoxylated C₈₋₁₈ mono- and diglycerides, (ii) an oil, and (iii) a metal oxide.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to a method comprising the step of contacting a formulation to a corn-based product from the ethanol production process to improve the separation of oil from at least one process stream (e.g., whole stillage and/or, thin stillage and/or syrup) generated as a by-product in corn to ethanol production. The process involves extraction of oil from milled corn and residues from the fermentation step, including thick stillage, distillers wet grain, distillers dry grain and distillers dry grains, with solubles. The method can be used in either a wet milling process or a dry milling process for ethanol production. Preferably the method is employed in a dry-milling process.

In particular, the invention provides a process for extracting corn oil from corn in an ethanol production process by obtaining a corn-based product from the ethanol production process and applying a formulation comprising

(i) a compound of formula (I),

wherein

R¹ is a fatty acid residue,

R² and R³ are the same or different and each is a polyalkoxy group or —C(O)R¹, provided that at least one of R² and R³ is a polyalkoxy group,

(ii) an oil, and

(iii) a metal oxide

to the corn-based product from an ethanol production process. The applying step can take place by any suitable method, including stirring (e.g., mechanical stirring), shearing, shaking, static mixing, whisking, mashing, vibrating, circulating, flowing, boiling, spraying, or any combination thereof.

Typically the combined mixture of the corn-based product and formulation are heated during the applying step. The temperature should be sufficient to facilitate the recovery of oil from the corn-based product. For example, the mixture can be heated to 30-110° C. (e.g., 40-100° C., 50-100° C., 60-90° C., 70-90° C., 80-90° C.). In some embodiments, the mixture is heated to about 90° C., about 85° C., about 80° C., or about 75° C. Preferably, the mixture is heated to about 85° C.

The applying step can take place over any suitable time period that is appropriate for maximizing the recovery of oil. Typically, the applying step will be at least 1 minute (e.g., at least 2 minutes, at least 3 minutes, at least 5 minutes, at least 8 minutes, at least 10 minutes, at least 15 minutes), but generally less than 120 minutes (e.g., less than 90 minutes, less than 75 minutes, less than 60 minutes, less than 45 minutes, less than 30 minutes, less than 20 minutes, less than 15 minutes, less than 12 minutes, less than 10 minutes, less than 8 minutes, less than 5 minutes). These suggested lower and upper limits with respect to the length of time can be used in any combination to describe the range of the second temperature, or can be used singly to describe an open-ended range.

After the formulation has been applied to the corn-based product, the oil can be quantified, isolated, and/or purified by any suitable technique (e.g., centrifugation, physical extraction, solvent extraction, super critical fluid extraction, filtration, dissolution, fractionation, or any combination of these techniques).

The corn can be any type of corn that undergoes processing to obtain ethanol and/or oil. For example, the corn can be dent corn (also known as field corn), sweet corn, flint corn, popcorn, waxy corn (also known as maize), high oil corn, or hybrids thereof. Typically the corn will be dent corn.

In a typical dry milling process, corn oil passes through the fermentation and distillation processes and can be found in the thick (whole) stillage product, which is typically further separated into thin stillage and wet grains (wet cake) The thin stillage is processed to concentrate the composition into syrup. At this stage of the process, about half of the oil is in the distillers wet grain (DWG) and the other half is found in the syrup. The concentrated syrup can be processed to separate the oil from the syrup; the remaining syrup can be combined with the distillers wet grain (DWG) and dried to form dry distillers grain (DDG). The method can be performed at any suitable point of the ethanol production process, including after the corn has been milled (e.g., before fermentation), after thick stillage has been formed, after thin stillage has been formed, after distillers wet grains (DWG) (wet cake) have been formed, and/or after distillers dry grains with solubles (DDGS) have been formed. As it will be appreciated, the method can be performed at one point of the ethanol production process or at multiple points of the ethanol production process. Moreover, if necessary, the method can be repeated one or more times to increase the percent recovery of oil from a desired corn-based product.

In view of the flexibility of the method, the corn-based product can be in one or more forms. For example, the corn-based product can be milled corn, thick stillage, thin stillage, syrup, distillers wet grain (DWG), distillers dry grain (DDG), distillers dry grains with soluble (DDGS), or any combination thereof. In an aspect, the formulation is applied to a thick (whole) stillage, thin stillage, or syrup corn-based product. Preferably, the corn-based product is thin stillage.

The method described herein generally provides an increase in percent corn oil recovery relative to the use of no formulation. More specifically, the percent corn oil recovery is increased when the formulation is applied to the corn-based product compared to when no formulation and/or additive is applied to the same corn-based product. In some aspects, the percent corn oil recovery is at least 5% or more (e.g., at least 5.5% or more, at least 6% or more, at least 6.5% or more, at least 7% or more).

In the formulation to be applied to the corn-based product, the compound of formula (I) is an alkoxylated glycerine ester (e.g., ethoxylated mono- or diglyceride), such as alkoxylated glycerine esters derived from one or more fatty acid residues.

In the compound of formula (I), R¹ and optionally one of R² and R³ comprise a fatty acid residue that can be saturated or unsaturated and either straight chain or branched. Fatty acids typically have an even number of carbon atoms and can range from 4 to 28 carbons. If the fatty acid residue is unsaturated, the double bond(s) can have either a cis or trans configuration. Suitable fatty acid residues include residues of butyric acid, caprylic acid, oleic acid, linoleic acid, linoeladic acid, linolenic acid, stearic acid, palmitic acid, palmitoleic acid, sapienic acid, myristic acid, myristoleic acid, lauric acid, arachidic acid, arachidonic acid, behenic acid, lignoceric acid, cerotic acid, erucic acid, elaidic acid, vaccenic acid, eicosapentaenoic acid, docosahexaenoic acid, and combinations thereof. In an embodiment, the fatty acid residue is a residue of oleic acid, lauric acid, stearic acid, palmitic acid, or a combination thereof.

In some embodiments, R¹ is a saturated or unsaturated, straight or branched alkyl C₇₋₂₂ chain (e.g., a C₈₋₂₁ chain, a C₁₀₋₂₀ chain, a C₁₂₋₁₈ chain, or a C₁₄₋₁₈ chain). In other words, R¹ preferably comprises at least 7 carbon atoms (e.g., at least 8 carbon atoms, at least 10 carbon atoms, at least 12 carbon atoms, at least 14 carbon atoms, at least 16 carbon atoms, at least 18 carbon atoms, or at least 20 carbon atoms) and less than 22 carbon atoms (e.g., less than 20 carbon atoms, less than 18 carbon atoms, less than 16 carbon atoms, less than 14 carbon atoms, less than 12 carbon atoms, less than 10 carbon atoms, or less than 8 carbon atoms). These suggested lower and upper limits with respect to the number of carbons in the alkyl chain of R¹ can be used in any combination to define a close-ended range.

R² and R³ are the same or different and each is a polyalkoxy group or —C(O)R¹, provided that at least one of R² and R³ is a polyalkoxy group. In some embodiments, both R² and R³ are a polyalkoxy group. In other embodiments, one of R² and R³ is —C(O)R¹ and the other is a polyalkoxy group. When R² and/or R³ is —C(O)R¹, the definition of R¹ is the same as set forth above. While the saturated or unsaturated, straight or branched alkyl chain of R¹ and either R² or R³ can be identical, the alkyl chains of these substituents do not necessarily need to be the same. In a preferred embodiment, the alkyl chains of R¹ and either R² or R³ are different.

The polyalkoxy group can be based on any suitable carbon range, e.g., C₂₋₆, C₂₋₅, C₂₋₄, C₂₋₃, C₃, or C₂. For example, the polyalkoxy group can be polyethoxy (—(CH₂CH₂O)_(n)H), polypropoxy (e.g., —(CH₂CH(CH₃)O)_(n)H or —(CH(CH₃)CH₂O)_(n)H), or a combination thereof, in which n is 2-40. In an embodiment, the polyalkoxy group is a polyethoxy group comprising up to 40 moles of ethylene oxide.

The polyalkoxy group can comprise 2-40 moles alkoxylation per compound of formula (I). For example, the polyalkoxy group can comprise at least 2 moles (e.g., at least 4 moles, at least 8 moles, at least 10 moles, at least 15 moles, at least 20 moles, at least 22 moles, at least 23 moles, at least 25 moles, at least 28 moles, at least 30 moles, at least 32 moles, at least 34 moles, at least 36 moles, or at least 38 moles) and less than 40 moles (e.g., less than 38 moles, less than 36 moles, less than 34 moles, less than 32 moles, less than 30 moles, less than 28 moles, less than 25 moles, less than 23 moles, less than 22 moles, less than 20 moles, less than 15 moles, less than 10 moles, less than 8 moles, or less than 4 moles) alkoxylation per compound of formula (I). These suggested lower and upper limits with respect to the moles of alkoxylation per compound of formula (I) can be used in any combination to define a close-ended range. In some aspects, the polyalkoxy group comprises 20-25 moles (e.g., 20 moles, 21 moles, 22 moles, 23 moles, 24 moles, and 25 moles) alkoxylation (e.g., ethoxylation) per compound of formula (I).

The molecular weight of the alkoxylated portion is not particularly limited. Preferably, the molecular weight of the alkoxylated (e.g., ethoxylated) portion is set so as to provide a liquid formulation comprising (i), (ii), (iii), and any optional additives. For example, the number, weight, or volume average molecular weight can be at least about 200 g/mol (e.g., at least about 300 g/mol, at least about 400 g/mol, at least about 500 g/mol, at least about 800 g/mol, at least about 1,000 g/mol, at least about 1,500 g/mol, at least about 2,000 g/mol) and/or up to about 10,000 g/mol (e.g., up to about 9,000 g/mol, up to about 8,000 g/mol, up to about 7,000 g/mol, up to about 6,000 g/mol, up to about 5,000 g/mol, up to about 4,000 g/mol, up to about 3,000 g/mol, up to about 2,000 g/mol, or up to about 1,000 g/mol). These suggested lower and upper limits with respect to the number, weight, or volume average molecular weight can be used in any combination to describe the polymer molecular weight range (e.g., about 200 to about 10,000 g/mol, about 300 g/mol to about 5,000 g/mol, and about 1,000 to about 2,000 g/mol, etc.).

While the compound of formula (I) defines a single compound, in some aspects, the formulation will comprise more than one compound of formula (I) to form a mixture of compounds defined by formula (I). For example, the mixture of compounds defined by formula (I) can include ethoxylated C₈₋₁₈ mono- and diglycerides (e.g., C₁₄₋₁₈ mono- and diglycerides) or a mixture of laurate, oleate, stearate, and/or palmitate partial esters of glycerine.

The compound of formula (I) or a mixture thereof can be synthesized by any suitable method or purchased commercially. For example, a compound of formula (I) can be produced by saponifying and/or transesterifying a glyceride material, such as canola oil, cottonseed oil, corn oil, poppyseed oil, sunflower oil, safflower oil, linseed oil, peanut oil, or soybean oil. Production methods of ethoxylated monoglycerides are known in the art. See, e.g., U.S. Pat. No. 3,433,645, the entire disclosure of which is incorporated by reference.

Commercially available compounds of formula (I) or a mixture thereof include, e.g., LUMULSE™ products (Lambent Technologies, Gurnee, Ill.) and ALDOSPERSE™ products (Lonza, Allendale, N.J.). Specific products include LUMULSE™ POE (20) GMS K and ALDOSPERSE™ MS-20 KFG.

The oil in the formulation is any suitable liquid oil. Typically the oil should be of a grade that is certified GRAS, however, not all instances require such grade. Suitable oils include a petroleum distillate (e.g., white mineral oil, pale oil, paraffinic oil, and combinations thereof), a vegetable oil (e.g., soybean oil, castor oil, canola oil, rapeseed oil, linseed oil, sunflower oil, safflower oil, cottonseed oil, and combinations thereof), or a combination thereof. Mineral oil (also known as white oil, liquid paraffin, pariffinum liquidum, liquid petroleum, and baby oil) is especially preferred.

The metal oxide in the formulation is any compound comprising at least one metal atom and at least one anion of oxygen that has an oxidation state of −2. In some aspects, the metal oxide is selected from the group consisting of silicon dioxide (including fumed silica, amorphous silica, precipitated silica, hydrophilic silica, and hydrophobic silica), titanium dioxide, zinc oxide, iron oxide, aluminum oxide, cerium oxide, zirconium oxide, and a combination thereof. Preferably the metal oxide is silicon dioxide.

The average particle size of the metal oxide is not particularly limited and can range from 1 nm to 10 μm. For example, the average particle size of the metal oxide can be at least 1 nm (e.g., at least 10 nm, at least 30 nm, at least 50 nm, at least 75 nm, at least 100 nm, at least 200 nm, at least 300 nm, at least 400 nm, at least 500 nm, at least 600 nm, at least 700 nm, at least 800 nm, at least 900 nm, at least 1 μm, at least 2 μm, at least 3 μm, at least 4 μm, at least 5 μm, at least 6, at least 7 μm, at least 8 μm, or at least 9 μm). The average particle size of the metal oxide typically is less than 10 μm (e.g., less than 9 μm, less than 8 μm, less than 7 μm, less than 6 μm, less than 5 μm, less than 4 μm, less than 3 μm, less than 2 μm, less than 1 μm, less than 900 nm, less than 800 nm, less than 700 nm, less than 600 nm, less than 500 nm, less than 400 nm, less than 300 nm, less than 200 nm, less than 100 nm, less than 75 nm, less than 50 nm, less than 30 nm, less than 10 nm, or less than 1 nm). These suggested lower and upper limits with respect to the average particle size of the metal oxide can be used in any combination to define a close-ended range.

In some embodiments, the formulation can further comprise additional components.

For example, the formulation can optionally comprise a triglyceride that corresponds to the alkoxylated mono- or diglyceride of formula (I) (e.g., the oleate ester made from canola oil). The upper limit of the amount of triglyceride that can be present is not particularly limited, but can be up to 5 wt % (e.g., less than 4.5 wt %, less than 4 wt %, less than 3.5 wt %, less than 3 wt %, less than 2.5 wt %, less than 2 wt %, less than 1.5 wt %, less than 1 wt %, or less than 0.5 wt %).

For example, the formulation can optionally comprise glycerine in an amount up to 10 wt % (e.g., less than 9 wt %, less than 8 wt %, less than 7 wt %, less than 6 wt %, less than 5 wt %, less than 4 wt %, less than 3 wt %, less than 2 wt %, or less than 1 wt %).

The formulation can also optionally comprise one or more glycerine esters (e.g., a monoglyceride, a diglyceride, a triglyceride, or a combination thereof) in an amount up to 5 wt % (e.g., less than 4.5 wt %, less than 4 wt %, less than 3.5 wt %, less than 3 wt %, less than 2.5 wt %, less than 2 wt %, less than 1.5 wt %, less than 1 wt %, or less than 0.5 wt %). The fatty acid residues that form the glycerine ester are as described herein.

The formulation can optionally comprise a diol, such as propylene glycol or ethylene glycol, in an amount up to 7 wt % (e.g., less than 6 wt %, less than 5 wt %, less than 4 wt %, less than 3 wt %, less than 2 wt %, less than 1 wt %, or less than 0.5 wt %).

In one aspect of the invention, the formulation is substantially devoid of a component derived from a sorbitol, a sorbitan, or isosorbide. As used herein, “substantially devoid of a component derived from a sorbitol, a sorbitan, or isosorbide” refers to a formulation that contains less than about 5 wt % of a component derived from a sorbitol, a sorbitan, or isosorbide. For example, less than about 4 wt %, less than about 3 wt %, less than about 2 wt %, less than about 1 wt %, less than about 0.5 wt %, or less than about 0.1 wt % by weight of a component derived from a sorbitol, a sorbitan, or isosorbide is present in the formulation. In some embodiments, the formulation does not comprise a component derived from a sorbitol, a sorbitan, or isosorbide. In some embodiments, the formulation does not comprise a polysorbate (e.g., polysorbate 20, polysorbate 40, polysorbate 60, polysorbate 65, or polysorbate 80), a sorbitan (e.g., sorbitan monolaurate, sorbitan monooleate, or sorbitan monostearate), or sorbitol.

The formulation can comprise (i) a compound of formula (I) or a mixture thereof, (ii) an oil, and (iii) a metal oxide in any amounts so long as the resulting formulation is effective for recovering oil from a corn-based product from an ethanol production process. The only caveat is that the amounts of compound of formula (I) or a mixture thereof, oil, and metal oxide add up to 100 wt %. If the formulation includes one or more additional components, such as an alkoxylated triglyceride, glycerol, a diol, and/or one or more glycerine esters, the amounts of (i), (ii), (iii), and the one or more additional components add up to 100 wt %.

The compound of formula (I) or a mixture thereof can be present in any suitable amount. In some embodiments, the compound or mixture thereof is present in an amount of about 20-75 wt %. Thus, the compound or mixture thereof is present in an amount of at least 20 wt % (e.g., at least 25 wt %, at least about 30 wt %, at least about 35 wt %, at least about 40 wt %, at least about 45 wt %, at least about 50 wt %, at least about 55 wt %, at least about 60 wt %, at least about 65 wt %, or at least 70 wt %) and less than 75 wt % (e.g., less than about 70 wt %, less than about 65 wt %, less than about 60 wt %, less than about 55 wt %, less than about 50 wt %, less than about 45 wt %, less than about 40 wt %, less than about 35 wt %, or less than about 30 wt %). These suggested lower and upper limits with respect to the amount of a compound of formula (I) or a mixture thereof can be used in any combination to define a close-ended range. For example, the composition can comprise about 25-70 wt %, about 35-55 wt %, about 40-55 wt %, about 40-50 wt %, about 40-65 wt %, or about 50 wt % of a compound of formula (I) or a mixture thereof.

The oil or a combination of oils can be present in the composition in any suitable amount, such as about 25-74 wt %. Thus, the total amount of oil is present in an amount of at least 25 wt % (e.g., at least about 30 wt %, at least about 35 wt %, at least about 40 wt %, at least about 45 wt %, at least about 50 wt %, at least about 55 wt %, at least about 60 wt %, at least about 65 wt %, or at least about 70 wt %) and less than 74 wt % (e.g., less than about 70 wt %, less than about 65 wt %, less than about 60 wt %, less than about 55 wt %, less than about 50 wt %, less than about 45 wt %, less than about 40 wt %, less than about 35 wt %, or less than about 30 wt %). These suggested lower and upper limits with respect to the amount of oil can be used in any combination to define a close-ended range. For example, the composition can comprise about 30-70 wt %, about 25-63 wt %, about 25-61 wt %, about 30-60 wt %, about 41-63 wt %, about 43-61 wt %, about 45-55 wt %, about 45-50 wt %, or about 46-48 wt % of an oil or a combination of oils.

The metal oxide or a combination thereof can be present in the composition in any suitable amount, such as about 1-5 wt %. Thus, the total amount of metal oxide is present in an amount of at least 1 wt % (e.g., at least about 1.5 wt %, at least about 2 wt %, at least about 2.5 wt %, at least about 3 wt %, at least about 3.5 wt %, at least about 4 wt %, or at least about 4.5 wt %) and less than 5 wt % (e.g., less than about 4.5 wt %, less than about 4 wt %, less than about 3.5 wt %, less than about 3 wt %, less than about 2.5 wt %, less than about 2 wt %, less than about 1.5 wt %, or less than about 1 wt %). These suggested lower and upper limits with respect to the amount of metal oxide can be used in any combination to define a close-ended range. For example, the composition can comprise about 2-4 wt %, 2-3 wt %, about 2 wt %, or about 3 wt % of metal oxide or a combination thereof.

The present invention is directed to a formulation comprising (i) a mixture of compounds defined by formula (I) comprising ethoxylated C₈₋₁₈ mono- and diglycerides, (ii) an oil, and (iii) a metal oxide. The oil and metal oxide are as described herein. In an aspect, this formulation comprises:

50 wt % of (i), 46-48 wt % of (ii), and 2-4 wt % of (iii),

63 wt % of (i), 35 wt % of (ii), and 2 wt % of (iii),

55 wt % of (i), 43 wt % of (ii), and 2 wt % of (iii),

54 wt % of (i), 43 wt % of (ii), and 3 wt % of (iii),

55 wt % of (i), 43 wt % of (ii), and 2 wt % of (iii),

50 wt % of (i), 48 wt % of (ii), and 2 wt % of (iii),

50 wt % of (i), 47 wt % of (ii), and 3 wt % of (iii)

40 wt % of (i), 58 wt % of (ii), and 2 wt % of (iii), or

40 wt % of (i), 57 wt % of (ii), and 3 wt % of (iii).

In any of the embodiments of this formulation, the oil can be mineral oil or the metal oxide can be silicon dioxide or a combination of both features.

The formulations described herein can be prepared by any suitable method. In general, the metal oxide (e.g., silicon dioxide) is pre-mixed in a portion of the oil (e.g., mineral oil). The compound of formula (I) or a mixture thereof is then blended with the metal oxide/oil premix, and the remaining portion of oil. The resulting composition is mixed well, optionally heated (e.g., up to 150° C., up to 130° C., up to 120° C., up to 110° C., up to 100° C., etc.), processed through a homogenizer to provide a uniform (or nearly uniform) particle size, and filtered.

In a preferred embodiment, the formulation is a liquid at room temperature. Accordingly, in such embodiments, the formulation should not be a gel, solid, or semi-solid at room temperature.

The following examples further illustrate the invention but, of course, should not be construed as in any way limiting its scope.

Example 1

This example demonstrates a method of corn oil recovery from a corn-based product using an ethanol production process in an embodiment of the invention.

On an analytical balance, 0.05 to 0.07 g of a formulation (“defoamer”) (0.05 wt % of the total sample) was weighed into a 250 ml beaker. The appropriate amount of corn syrup was added, which ranged from 100 g for 0.05 g of defoamer to 140 g for 0.07 g of defoamer. A stir bar was added, and the defoamer/corn syrup mixture was placed on a hot plate. The mixture was agitated sufficiently to form a vortex, heated to 85° C., and held at that temperature for 5 minutes.

After heating for 5 minutes, the beaker was removed and the contents were poured into a small centrifuge tube with the defoamer/corn oil syrup mixture to about the top of the tube. The tube was not overfilled, so that the top of the sample was viewable in the centrifuge tube when the cap of the centrifuge tube is on. The tube was centrifuged for 10 minutes.

After 10 minutes, the tube was removed from the centrifuge and the contents were left undisturbed for 1 hour.

The total height (mm) of the sample (corn oil portion and the rest of the sample) and the total height (mm) of just the corn oil portion of the sample were measured and recorded. The corn oil portion was measured as a height (mm) and as a % recovery. The results are set forth in the following Tables 1-10.

TABLE 1 CEA2 CEA5 CEA7 Corn Oil Sample 4490 Blank Blank 8330 8331 8312 Polysorbate 80 40 43.5 Canola Oil 34 Hydrophobic Silica 6 6 6.5 Ethoxylated mono & 45 45 45 diglycerides Ethoxylated stearic acid 4 Polysorbate 65 5 Mono & diglycerides, 5 5 5 liquid, low mono Propylene Gycol 5 Centrifuge, Large Amount Defoamer 0 0 0.0632 0.068 0.0548 Amount Corn Syrup 125 120 126.4 136 109.6 Total Height (mm) 92 97 98 100 102 Height Corn Oil (mm) 2 4 6 7 7 % Corn Oil 2.51 4.12 6.12 7 6.86 Centrifuge, Small Total Height (mm) 108 105 107 106 108 Height Corn Oil (mm) 2 3 6 6 6.5 % Corn Oil 1.85 2.86 5.61 5.66 6.02

TABLE 2 Corn Oil Sample 4813 Blank 9493 R4 9493 R5 9493 R6 9494 R7 9494 R8 Canola Oil 29.8 29.8 White mineral Oil Technical White Oil Hydrophobic Silica 3.5 3.5 3.5 5.2 5.2 Ethoxylated mono & diglycerides 5 5 5 5 30 Silicon Dioxide Mono & diglycerides, liquid, low mono 5 5 5 5 5 Polyglycerol oleate 25 25 25 Decaglycerol decaoleate Polyglycol oleate transester 56.5 81.5 56.5 25 25 Propylene Glycol 5 5 5 5 5 Sorbitol, 70% or 80% Sorbitan monolaurate Glycerine Ethoxylated Stearic Acid Amount Defoamer 0 0.0696 0.0632 0.0704 0.0565 0.0613 Amount Corn Syrup 130 139.2 126.4 140.8 113 122.6 Centrifuge, Small Total Height (mm) 106 106 107 107 107 108 Height Corn Oil (mm) 5 6 7 7 7.5 7.5 % Corn Oil 4.72 5.66 6.54 6.54 7.01 6.94 Corn Oil Sample 4813 9494 R9 9493 R4 9493 R5 9493 R6 9494 R7 9494 R8 Canola Oil 29.8 29.8 White mineral Oil Technical White Oil Hydrophobic Silica 3.5 3.5 3.5 3.5 5.2 5.2 Ethoxylated mono & diglycerides 55 5 5 5 5 30 Silicon Dioxide Mono & diglycerides, liquid, low mono 5 5 5 5 5 5 Polyglycerol oleate 25 25 25 Decaglycerol decaoleate Polyglycol oleate transester 31.5 56.5 81.5 56.5 25 25 Propylene Glycol 5 5 5 5 5 5 Sorbitol, 70% or 80% Sorbitan monolaurate Glycerine Ethoxylated Stearic Acid Amount Defoamer 0.0596 0.0675 0.0599 0.0605 0.0657 0.0597 Amount Corn Syrup 119.2 135 119.8 121 131.4 119.4 Centrifuge, Small Total Height (mm) 107 105 105 106 108 108 Height Corn Oil (mm) 7 7 7 7 7.5 7 % Corn Oil 6.54 6.67 6.67 6.6 6.94 6.48

TABLE 3 Corn Oil Sample 4813 9494 R9 Blank 9618 R1 9618 R3 9577 R1 9577 R2 Canola Oil White mineral Oil 50 Technical White Oil 50 Hydrophobic Silica 3.5 Ethoxylated mono & diglycerides 55 100 50 50 50 Silicon Dioxide Mono & diglycerides, liquid, low mono 5 Polyglycerol oleate Decaglycerol decaoleate Polyglycol oleate transester 31.5 50 Propylene Glycol 5 Sorbitol, 70% or 80% Sorbitan monolaurate Glycerine Ethoxylated Stearic Acid Amount Defoamer 0.0809 0 0.0614 0.0656 0.077 0.0646 Amount Corn Syrup 161.8 130 122.8 131.2 154 129.2 Centrifuge, Small Total Height (mm) 107 107 107 103 105 106 Height Corn Oil (mm) 7 4 4 4.5 4 5 % Corn Oil 6.54 3.74 3.74 4.37 3.81 4.72 Corn Oil Sample 4813 9577 R3 9577 R4 9578 R5 9578 R6 9578 R7 9578 R8 Canola Oil White mineral Oil 40 40 30 27 27 Technical White Oil 30 Hydrophobic Silica 13 13 Ethoxylated mono & diglycerides 47 47 30 30 30 30 Silicon Dioxide 13 13 Mono & diglycerides, liquid, low mono 10 10 10 10 Polyglycerol oleate Decaglycerol decaoleate Polyglycol oleate transester 30 20 20 30 Propylene Glycol Sorbitol, 70% or 80% Sorbitan monolaurate Glycerine Ethoxylated Stearic Acid Amount Defoamer 0.0595 0.0832 0.0726 0.0697 0.0693 0.0546 Amount Corn Syrup 119 166.4 145.2 139.4 138.6 109.2 Centrifuge, Small Total Height (mm) 106 103 104 106 104 105 Height Corn Oil (mm) 7 6.5 6 6.5 7 6 % Corn Oil 6.6 6.31 5.77 6.13 6.73 5.71

TABLE 4 Corn Oil Sample 4813 9579 9577 9577 9578 9578 R10 R3 R4 R6 R7 R11 Canola Oil White mineral Oil 40 40 27 27 Technical White Oil 27 Hydrophobic Silica 13 13 Ethoxylated mono & diglycerides 25 47 47 30 30 20 Silicon Dioxide 13 13 13 Mono & diglycerides, liquid, low mono 5 10 10 10 Polyglycerol oleate Decaglycerol decaoleate Polyglycol oleate transester 20 20 30 Propylene Glycol Sorbitol, 70% or 80% 40 Sorbitan monolaurate 25 Glycerine 5 Ethoxylated Stearic Acid Amount Defoamer 0.0599 0.0731 0.065 0.06 0.061 0.0725 Amount Corn Syrup 119.8 146.2 130 120 122 145 Centrifuge, Small Total Height (mm) 105 105 103 105 105 103 Height Corn Oil (mm) 6 7 7 7 7 6 % Corn Oil 5.71 6.67 6.8 6.67 6.67 5.83 Corn Oil Sample 4813 9630 9630 9581 9631 9631 R12 R16 R18 R20 R22 R24 Canola Oil White mineral Oil 32.8 Technical White Oil 27 30 32.2 Hydrophobic Silica 7.2 Ethoxylated mono & diglycerides 20 87 57 20 93.5 61.3 Silicon Dioxide 13 13 13 6.5 6.5 Mono & diglycerides, liquid, low mono 10 Polyglycerol oleate Decaglycerol decaoleate Polyglycol oleate transester Propylene Glycol 10 5 Sorbitol, 70% or 80% 35 Sorbitan monolaurate 20 Glycerine Ethoxylated Stearic Acid Amount Defoamer 0.0746 0.078 0.0698 0.0563 0.0586 0.0585 Amount Corn Syrup 149.2 156 139.6 112.6 117.2 117 Centrifuge, Small Total Height (mm) 105 104 103 104 105 105 Height Corn Oil (mm) 7 7 6 7 7 6.5 % Corn Oil 6.67 6.73 5.83 6.73 6.67 6.19

TABLE 5 Corn Oil Sample 4813 9632 9632 9631 9631 9585 Blank R26 R28 R22 R24 R29 Canola Oil White mineral Oil Technical White Oil 33 32.2 35 Hydrophobic Silica Ethoxylated mono & diglycerides 96 63 93.5 61.3 25 Silicon Dioxide 4 4 6.5 6.5 3 Mono & diglycerides, liquid, low mono 10 Polyglycerol oleate Decaglycerol decaoleate Polyglycol oleate transester Propylene Glycol Sorbitol, 70% or 80% Sorbitan monolaurate 17 Glycerine Ethoxylated Stearic Acid 10 Amount Defoamer 0 0.0544 0.0596 0.0587 0.0618 0.0762 Amount Corn Syrup 120 108.8 119.2 117.4 123.6 152.4 Centrifuge, Small Total Height (mm) 105 105 106 106 105 104 Height Corn Oil (mm) 4.5 7 7 7 7 6 % Corn Oil 4.29 6.67 6.6 6.6 6.67 5.77 Corn Oil Sample 4813 9585 9633 9633 9633 963.3 9639 R30 R31 R32 R31 R32 R39 Canola Oil White mineral Oil Technical White Oil 35 35 35 Hydrophobic Silica Ethoxylated mono & diglycerides 17 98 63 98 63 98 Silicon Dioxide 3 2 2 2 2 2 Mono & diglycerides, liquid, low mono 10 Polyglycerol oleate Decaglycerol decaoleate Polyglycol oleate transester Propylene Glycol Sorbitol, 70% or 80% 25 Sorbitan monolaurate Glycerine Ethoxylated Stearic Acid 10 Amount Defoamer 0.079 0.0601 0.0667 0.0625 0.0734 0.0603 Amount Corn Syrup 158 120.2 123.4 125 146.8 120.6 Centrifuge, Small Total Height (mm) 106 105 106 107 106 107 Height Corn Oil (mm) 6 7 7 7 6.5 7 % Corn Oil 5.66 6.67 6.6 6.54 6.13 6.54

TABLE 6 Corn Oil Sample 4813 9639 9639 9639 9639 9639 9639 R40 R41 R42 R43 R44 R45 Canola Oil White mineral Oil 43 43 Technical White Oil 35 43 43 48 Hydrophobic Silica Ethoxylated mono & diglycerides 63 55 54 55 54 50 Silicon Dioxide 2 2 3 2 3 2 Mono & diglycerides, liquid, low mono Polyglycerol oleate Decaglycerol decaoleate Polyglycol oleate transester Propylene Glycol Sorbitol, 70% or 80% Sorbitan monolaurate Glycerine Ethoxylated Stearic Acid Amount Defoamer 0.0756 0.055 0.0543 0.0547 0.0566 0.0574 Amount Corn Syrup 141.2 110 108.6 109.4 113.2 114.8 Centrifuge, Small Total Height (mm) 107 108 107 108 106 107 Height Corn Oil (mm) 6 7 7 7 7 7 % Corn Oil 5.6 6.48 6.54 6.48 6.6 6.54 Corn Oil Sample 4813 9639 9642 9642 9642 9642 9642 R46 R47 R48 R49 R50 R51 Canola Oil White mineral Oil 58 57 53 52 43 Technical White Oil 47 Hydrophobic Silica Ethoxylated mono & diglycerides 50 40 40 45 45 55 Silicon Dioxide 3 2 3 2 3 2 Mono & diglycerides, liquid, low mono Polyglycerol oleate Decaglycerol decaoleate Polyglycol oleate transester Propylene Glycol Sorbitol, 70% or 80% Sorbitan monolaurate Glycerine Ethoxylated Stearic Acid Amount Defoamer 0.057 0.0649 0.094 0.0714 0.0747 0.0575 Amount Corn Syrup 114 129.8 128.8 142.8 149.4 115 Centrifuge, Small Total Height (mm) 107 107 107 106 107 105 Height Corn Oil (mm) 7 7 7 7 7 6 % Corn Oil 6.54 6.54 6.54 6.6 6.54 5.71

TABLE 7 Corn Oil Sample 4813 9642 9651 9651 9652 9652 9652 R52 R53 R54 R55 R56 R57 Canola Oil White mineral Oil 42 40 40 47.5 42.8 47.5 Technical White Oil Hydrophobic Silica 2.5 2.2 2.5 Ethoxylated mono & diglycerides 55 55 55 50 55 50 Silicon Dioxide 3 Mono & diglycerides, liquid, low mono Polyglycerol oleate 5 Decaglycerol decaoleate 5 Polyglycol oleate transester Propylene Glycol Sorbitol, 70% or 80% Sorbitan monolaurate Glycerine Ethoxylated Stearic Acid Amount Defoamer 0.0549 0.0729 0.0505 0.0606 0.0623 Amount Corn Syrup 119.8 145.8 101 121.2 124.6 Centrifuge, Small Total Height (mm) 107 106 106 107 107 Height Corn Oil (mm) 7 7 7 7 7 % Corn Oil 6.54 6.6 6.6 6.54 6.54 Corn Oil Sample 4813 9652 9652 9652 9654 9654 9654 R58 R59 R60 R61 R62 R63 Canola Oil White mineral Oil 46.35 45.1 42.8 47 46.5 46 Technical White Oil Hydrophobic Silica 2.4 2.4 2.2 Ethoxylated mono & diglycerides 48.75 47.5 45 50 50 50 Silicon Dioxide 3 3.5 4 Mono & diglycerides, liquid, low mono Polyglycerol oleate Decaglycerol decaoleate Polyglycol oleate transester Propylene Glycol Sorbitol, 70% or 80% 2.5 Sorbitan monolaurate Glycerine 5 10 Ethoxylated Stearic Acid Amount Defoamer 0.0613 0.0539 0.0588 0.0762 Amount Corn Syrup 122.6 107.8 117.6 152.4 Centrifuge, Small Total Height (mm) 108 107 107 106 Height Corn Oil (mm) 7 7 7 7 % Corn Oil 6.48 6.54 6.54 6.6

TABLE 8 Corn Oil Sample 4559 Blank CE2 8330 CE5 8331 CE7 8332 CE20 8278 CE24 8280 CE25 8280 CE26 8280 Blank Blank Polysorbate 80 40 43.5 56 Canola Oil 34 29.8 29.8 29.8 29.8 Hydrophobic Silica 6 6 6.5 5.2 5.2 5.2 5.2 Polyglycerol oleate Polyglycerol oleate, transester Ethoxylated mono & 45 45 45 2.5 52 54 52 diglycerides Ethoxylated stearic 4 1.5 3 2 3 acid Polysorbate 65 5 Mono & diglycerides, 5 5 5 liquid Mono & diglycerides, 4 liquid, low mono Propylene Glycol 5 Glycerine 5 5 5 Oleic Acid 5 5 Soya lecithin 5 Centrifuge, Large Amount Defoamer n/a 0.0622 0.0701 0.0575 0.0853 0.0629 0.067 0.0672 n/a naa Amount Corn Syrup 120 124.4 140.2 115 170.6 125.8 134 134.4 125 122 Total Height (mm) 101 99 99 99 101 98 98 98 99 99 Height Corn Oil (mm) 4 6.5 7 7 6 6.5 6 2.5 % Corn Oil 3.96 6.57 7.07 7.07 6.93 6.12 6.63 6.12 2.53 4.04 Centrifuge, Small Total Height (mm) 109 107 106 109 108 107 107 106 107 107 Height Corn Oil (mm) 4 7 6 7 6.5 7 6 6.5 3 4 % Corn Oil 3.67 6.54 5.66 6.42 6.02 6.54 5.61 6.13 2.8 3.73

TABLE 9 Corn Oil Sample 4559 A33 A33 A34 A34 A35 A35 A36 A36 A21 A21 unmilled milled unmilled milled unmilled milled unmilled milled unmilled milled 8369 8369 8369 8369 8370 8370 8370 8370 8358 8358 Polysorbate 80 Canola Oil 29.8 29.8 29.8 29.8 29.8 29.8 Hydrophobic Silica 5.2 5.2 5.2 5.2 3.5 3.5 5.2 5.2 5,2 5.2 Polyglycerol oleate 25 25 Polyglycerol oleate, transester 25 25 56.5 56.5 25 25 54.8 54.8 Ethoxylated mono & 25 25 25 25 25 25 25 25 25 25 diglycerides Ethoxylated stearic acid Polysorbate 65 5 5 5 5 5 5 5 5 5 5 Mono & diglycerides, liquid Mono & diglycerides, 5 5 5 5 5 5 5 5 5 5 liquid, low mono Propylene Glycol 5 5 Glycerine 5 5 5 5 5 5 5 5 Oleic Acid Soya lecithin Centrifuge Large Amount Defoamer 0.0571 0.0633 0.0663 0.0602 0.0604 0.0717 0.057 0.0679 0.0602 0.0706 Amount Corn Syrup 114.2 126.6 132.6 120.4 120.8 143.4 114 135.8 120.4 141.2 Total Height (mm) 99 100 100 99 100 103 103 104 98 97 Height Corn Oil (mm) 6.5 6 6 6 6.5 6.5 6.5 6 6 6 % Corn Oil 6.57 6 6 6.06 5.96 6.31 6.31 5.77 6.12 6.19 Centrifuge, Small Total Height (mm) 108 108 109 107 109 107 109 106 105 105 Height Corn Oil (mm) 6 6 6.5 6 6.5 6 6.5 6 6 6 % Corn Oil 5.55 5.55 5.96 5.61 5.96 5.61 5.96 5.66 5.71 5.71

TABLE 10 Corn Oil Sample 4559 A22 A22 A23 A23 unmilled milled unmilied milled A33 A34 A40 A47 8358 8358 8358 8358 8380 8380 8382 86 19 Polysorbate 80 65.4 60.4 39.1 Carnola Oil 29.8 Hydrophobic Silica 3.5 3.5 5.2 5.2 4.6 4.6 5.2 5.9 Polyglycerol oleate 30 Polyglycerol oleate, transester 31.5 31.5 29.8 29.8 20 Ethoxylated mono & diglycerides 50 50 45 45 15 20 20 20 Ethoxylated stearic acid Polysorbate 65 5 5 5 5 5 5 5 5 Mono & diglycerides, liquid Mono & diglycerides, liquid, 5 5 5 5 5 5 5 5 low mono Propylene Glycol 5 5 5 Glycerine 10 10 5 5 5 Oleic Acid Soya lecithin Centrifuge, Large Amount Defoamer 0.0744 0.0578 0.0604 0.0631 0.0777 0.0706 0.0756 0.0599 Amount Corn Syrup 148.8 115.6 120.8 126.2 155.4 141.2 151.2 119.8 Total Height (mm) 98 96 98 96 99 98 99 98 Height Corn Oil (mm) 6.5 5.5 6 6 6 6.5 7 6.5 % Corn Oil 6.63 5.73 6.12 6.25 6.06 6.63 7.07 6.32 Centrifuge, Small Total Height (mm) 106 106 108 107 106 106 106 107 Height Corn Oil (mm) 6 5 5 5 6.5 6.5 6.5 7 % Corn Oil 5.66 4.71 4.63 4.67 6.13 6.13 6.13 6.54

All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

The use of the terms “a” and “an” and “the” and “at least one” and similar references in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of the term “at least one” followed by a list of one or more items (for example, “at least one of A and B”) is to be construed to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B), unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context. 

The invention claimed is:
 1. A method for recovering oil from corn in ethanol production, the method comprising applying a formulation comprising (i) a compound of formula (I),

wherein R¹ is a fatty acid residue; R² and R³ are the same or different and each is a polyalkoxy group or —C(O)R¹, provided that at least one of R² and R³ is a polyalkoxy group; (ii) an oil, and (iii) a metal oxide to a corn-based product from an ethanol production process.
 2. The method of claim 1, wherein the corn-based product is milled corn, thick stillage, thin stillage, syrup, distillers wet grain (DWG), distillers dry grain (DDG), distillers dry grains with soluble (DDGS), or any combination thereof.
 3. The method of claim 1, wherein the applying step is performed after the corn has been milled, after thick stillage has been formed, after thin stillage has been formed, after distillers wet grains (DWG) have been formed, and/or after distillers dry grains with solubles (DDGS) have been formed.
 4. The method of claim 1, wherein R¹ is a saturated or unsaturated, straight or branched alkyl C₇₋₂₂ chain.
 5. The method of claim 1, wherein R¹ is a saturated or unsaturated, straight or branched alkyl C₈₋₁₈ chain.
 6. The method of claim 1, wherein both R² and R³ are a polyalkoxy group.
 7. The method of claim 1, wherein one of R² and R³ is —C(O)R¹ and the other is a polyalkoxy group.
 8. The method of claim 1, wherein the polyalkoxy group is a polyethoxy group comprising up to 40 moles of ethylene oxide.
 9. The method of claim 1, wherein the fatty acid residue is a residue of lauric acid, oleic acid, stearic acid, palmitic acid, or a combination thereof.
 10. The method of claim 1, wherein the formulation comprises more than one compound of formula (I) to form a mixture of compounds defined by formula (I).
 11. The method of claim 10, wherein the mixture of compounds defined by formula (I) comprises ethoxylated C₁₋₁₈ mono- and diglycerides.
 12. The method of claim 1, wherein the oil is mineral oil, a vegetable oil, or a combination thereof.
 13. The method of claim 12, wherein the oil is mineral oil.
 14. The method of claim 1, wherein the metal oxide is selected from the group consisting of silicon dioxide, titanium dioxide, zinc oxide, iron oxide, aluminum oxide, cerium oxide, zirconium oxide, and a combination thereof.
 15. The method of claim 14, wherein the metal oxide is silicon dioxide.
 16. The method of claim 1, wherein the formulation comprises (i) 25-70 wt % of at least one compound of formula (I), (ii) 25-74 wt % of an oil, and (iii) 1-5 wt % of a metal oxide, wherein the amounts of (i), (ii), and (iii) add up to 100 wt % of the total formulation. 